Many varieties of aromatic high-performance polymers are known. See, e.g., Vriesema, U.S. Pat. No. 4,876,327, concerning polyesters and the references cited therein. Generally high performance polymers comprise repeating aromatic monomer units which form a polymer backbone linked by some chemical bond, such as an ether, an ester, or an amide linkage. The presence of the aromatic groups provide chemical stability, structural integrity, and a high degree of linearity, and thus crystallinity, to the polymer.
One known group of aromatic high-performance polymer is the polyamides, which comprise generally phenyl groups linked at their 1 and 4 positions by amide linkages. This combination of 1,4 linked phenyl groups produces a highly linear polymer chain, which in macroscopic form forms a material which exhibits unusually high tensile strength and stiffness. One form is sold under the tradename Kevlar.TM. and is used extensively in fiber form in fabrics and composites. Another group of aromatic high-performance polymers is the poly(arylene ether ketones), which comprise phenyl groups alternatively linked at their 1,4 positions by ether linkages and ketone linkages. These materials, known in the art as "PEEK" are used in injection molding applications and as the matrix component in composite materials. An additional known aromatic high-performance polymer group is the poly(benzoxazoles). These polymers comprise alternating units of di-oxazole-benzene covalently bonded to the 1 and 4 positions of a phenyl group. The rodlike structure of the polymer chain conveys exceptional structural properties and high crystallinity on the polymer; however, concomitant intractability limits the processing options and, accordingly, the range of applications for poly (benzoxazoles).
It is an object of the present invention to provide polymer analogs to the aforementioned aromatic polymers which have different physical, chemical, and processing characteristics to increase the range of applications for these types of materials.